Historically plague has been a major infectious disease afflicting human populations, leading to millions of deaths. The etiologic agent of plague is Yersinia pestis and infection with this pathogen can develop into a highly contagious pneumonic disease with almost 100% lethality. Continued outbreaks of plague, along with the suitability of Y. pestis for weaponization has heightened interest in developing a vaccine. Currently, there is no safe and effective vaccine against Y. pestis. 
Thus, there is a need to provide sources of vaccines and antigens for production of vaccines. Improved vaccine design and development, as well as methods of making and using such compositions of matter are needed which provide inexpensive and highly accessible sources of such therapeutic and/or prophylactic compositions.